.TH "decode.h" 3 "Wed Aug 2 2017" "Brotli" \" -*- nroff -*- .ad l .nh .SH NAME decode.h \- API for Brotli decompression\&. .SH SYNOPSIS .br .PP .SS "Macros" .in +1c .ti -1c .RI "#define \fBBROTLI_DECODER_ERROR_CODES_LIST\fP(BROTLI_ERROR_CODE, SEPARATOR) " .br .RI "\fITemplate that evaluates items of \fBBrotliDecoderErrorCode\fP\&. \fP" .ti -1c .RI "#define \fBBROTLI_LAST_ERROR_CODE\fP BROTLI_DECODER_ERROR_UNREACHABLE" .br .RI "\fIThe value of the last error code, negative integer\&. \fP" .in -1c .SS "Typedefs" .in +1c .ti -1c .RI "typedef enum \fBBrotliDecoderParameter\fP \fBBrotliDecoderParameter\fP" .br .RI "\fIOptions to be used with \fBBrotliDecoderSetParameter\fP\&. \fP" .ti -1c .RI "typedef struct BrotliDecoderStateStruct \fBBrotliDecoderState\fP" .br .RI "\fIOpaque structure that holds decoder state\&. \fP" .in -1c .SS "Enumerations" .SS "Functions" .in +1c .ti -1c .RI "\fBBrotliDecoderState\fP * \fBBrotliDecoderCreateInstance\fP (\fBbrotli_alloc_func\fP alloc_func, \fBbrotli_free_func\fP free_func, void *opaque)" .br .RI "\fICreates an instance of \fBBrotliDecoderState\fP and initializes it\&. \fP" .ti -1c .RI "\fBBrotliDecoderResult\fP \fBBrotliDecoderDecompress\fP (size_t encoded_size, const uint8_t encoded_buffer[encoded_size], size_t *decoded_size, uint8_t decoded_buffer[*decoded_size])" .br .RI "\fIPerforms one-shot memory-to-memory decompression\&. \fP" .ti -1c .RI "\fBBrotliDecoderResult\fP \fBBrotliDecoderDecompressStream\fP (\fBBrotliDecoderState\fP *state, size_t *available_in, const uint8_t **next_in, size_t *available_out, uint8_t **next_out, size_t *total_out)" .br .RI "\fIDecompresses the input stream to the output stream\&. \fP" .ti -1c .RI "void \fBBrotliDecoderDestroyInstance\fP (\fBBrotliDecoderState\fP *state)" .br .RI "\fIDeinitializes and frees \fBBrotliDecoderState\fP instance\&. \fP" .ti -1c .RI "const char * \fBBrotliDecoderErrorString\fP (\fBBrotliDecoderErrorCode\fP c)" .br .RI "\fIConverts error code to a c-string\&. \fP" .ti -1c .RI "\fBBrotliDecoderErrorCode\fP \fBBrotliDecoderGetErrorCode\fP (const \fBBrotliDecoderState\fP *state)" .br .RI "\fIAcquires a detailed error code\&. \fP" .ti -1c .RI "\fBBROTLI_BOOL\fP \fBBrotliDecoderHasMoreOutput\fP (const \fBBrotliDecoderState\fP *state)" .br .RI "\fIChecks if decoder has more output\&. \fP" .ti -1c .RI "\fBBROTLI_BOOL\fP \fBBrotliDecoderIsFinished\fP (const \fBBrotliDecoderState\fP *state)" .br .RI "\fIChecks if decoder instance reached the final state\&. \fP" .ti -1c .RI "\fBBROTLI_BOOL\fP \fBBrotliDecoderIsUsed\fP (const \fBBrotliDecoderState\fP *state)" .br .RI "\fIChecks if instance has already consumed input\&. \fP" .ti -1c .RI "\fBBROTLI_BOOL\fP \fBBrotliDecoderSetParameter\fP (\fBBrotliDecoderState\fP *state, \fBBrotliDecoderParameter\fP param, uint32_t value)" .br .RI "\fISets the specified parameter to the given decoder instance\&. \fP" .ti -1c .RI "const uint8_t * \fBBrotliDecoderTakeOutput\fP (\fBBrotliDecoderState\fP *state, size_t *size)" .br .RI "\fIAcquires pointer to internal output buffer\&. \fP" .ti -1c .RI "uint32_t \fBBrotliDecoderVersion\fP (void)" .br .RI "\fIGets a decoder library version\&. \fP" .in -1c .SH "Detailed Description" .PP API for Brotli decompression\&. .SH "Macro Definition Documentation" .PP .SS "#define BROTLI_DECODER_ERROR_CODES_LIST(BROTLI_ERROR_CODE, SEPARATOR)" .PP Template that evaluates items of \fBBrotliDecoderErrorCode\fP\&. Example: .PP .nf // Log Brotli error code\&. switch (brotliDecoderErrorCode) { #define CASE_(PREFIX, NAME, CODE) \ case BROTLI_DECODER ## PREFIX ## NAME: \ LOG(INFO) << "error code:" << #NAME; \ break; #define NEWLINE_ BROTLI_DECODER_ERROR_CODES_LIST(CASE_, NEWLINE_) #undef CASE_ #undef NEWLINE_ default: LOG(FATAL) << "unknown brotli error code"; } .fi .PP .SS "#define BROTLI_LAST_ERROR_CODE BROTLI_DECODER_ERROR_UNREACHABLE" .PP The value of the last error code, negative integer\&. All other error code values are in the range from \fBBROTLI_LAST_ERROR_CODE\fP to \fC-1\fP\&. There are also 4 other possible non-error codes \fC0\fP \&.\&. \fC3\fP in \fBBrotliDecoderErrorCode\fP enumeration\&. .SH "Typedef Documentation" .PP .SS "typedef enum \fBBrotliDecoderParameter\fP \fBBrotliDecoderParameter\fP" .PP Options to be used with \fBBrotliDecoderSetParameter\fP\&. .SS "typedef struct BrotliDecoderStateStruct \fBBrotliDecoderState\fP" .PP Opaque structure that holds decoder state\&. Allocated and initialized with \fBBrotliDecoderCreateInstance\fP\&. Cleaned up and deallocated with \fBBrotliDecoderDestroyInstance\fP\&. .SH "Enumeration Type Documentation" .PP .SS "enum \fBBrotliDecoderErrorCode\fP" .PP Error code for detailed logging / production debugging\&. See \fBBrotliDecoderGetErrorCode\fP and \fBBROTLI_LAST_ERROR_CODE\fP\&. .SS "enum \fBBrotliDecoderParameter\fP" .PP Options to be used with \fBBrotliDecoderSetParameter\fP\&. .PP \fBEnumerator\fP .in +1c .TP \fB\fIBROTLI_DECODER_PARAM_DISABLE_RING_BUFFER_REALLOCATION \fP\fP Disable 'canny' ring buffer allocation strategy\&. Ring buffer is allocated according to window size, despite the real size of the content\&. .SS "enum \fBBrotliDecoderResult\fP" .PP Result type for \fBBrotliDecoderDecompress\fP and \fBBrotliDecoderDecompressStream\fP functions\&. .PP \fBEnumerator\fP .in +1c .TP \fB\fIBROTLI_DECODER_RESULT_ERROR \fP\fP Decoding error, e\&.g\&. corrupted input or memory allocation problem\&. .TP \fB\fIBROTLI_DECODER_RESULT_SUCCESS \fP\fP Decoding successfully completed\&. .TP \fB\fIBROTLI_DECODER_RESULT_NEEDS_MORE_INPUT \fP\fP Partially done; should be called again with more input\&. .TP \fB\fIBROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT \fP\fP Partially done; should be called again with more output\&. .SH "Function Documentation" .PP .SS "\fBBrotliDecoderState\fP* BrotliDecoderCreateInstance (\fBbrotli_alloc_func\fP alloc_func, \fBbrotli_free_func\fP free_func, void * opaque)" .PP Creates an instance of \fBBrotliDecoderState\fP and initializes it\&. The instance can be used once for decoding and should then be destroyed with \fBBrotliDecoderDestroyInstance\fP, it cannot be reused for a new decoding session\&. .PP \fCalloc_func\fP and \fCfree_func\fP \fBMUST\fP be both zero or both non-zero\&. In the case they are both zero, default memory allocators are used\&. \fCopaque\fP is passed to \fCalloc_func\fP and \fCfree_func\fP when they are called\&. .PP \fBParameters:\fP .RS 4 \fIalloc_func\fP custom memory allocation function .br \fIfree_func\fP custom memory fee function .br \fIopaque\fP custom memory manager handle .RE .PP \fBReturns:\fP .RS 4 \fC0\fP if instance can not be allocated or initialized .PP pointer to initialized \fBBrotliDecoderState\fP otherwise .RE .PP .SS "\fBBrotliDecoderResult\fP BrotliDecoderDecompress (size_t encoded_size, const uint8_t encoded_buffer[encoded_size], size_t * decoded_size, uint8_t decoded_buffer[*decoded_size])" .PP Performs one-shot memory-to-memory decompression\&. Decompresses the data in \fCencoded_buffer\fP into \fCdecoded_buffer\fP, and sets \fC*decoded_size\fP to the decompressed length\&. .PP \fBParameters:\fP .RS 4 \fIencoded_size\fP size of \fCencoded_buffer\fP .br \fIencoded_buffer\fP compressed data buffer with at least \fCencoded_size\fP addressable bytes .br \fIdecoded_size\fP \fBin:\fP size of \fCdecoded_buffer\fP; .br \fBout:\fP length of decompressed data written to \fCdecoded_buffer\fP .br \fIdecoded_buffer\fP decompressed data destination buffer .RE .PP \fBReturns:\fP .RS 4 \fBBROTLI_DECODER_RESULT_ERROR\fP if input is corrupted, memory allocation failed, or \fCdecoded_buffer\fP is not large enough; .PP \fBBROTLI_DECODER_RESULT_SUCCESS\fP otherwise .RE .PP .SS "\fBBrotliDecoderResult\fP BrotliDecoderDecompressStream (\fBBrotliDecoderState\fP * state, size_t * available_in, const uint8_t ** next_in, size_t * available_out, uint8_t ** next_out, size_t * total_out)" .PP Decompresses the input stream to the output stream\&. The values \fC*available_in\fP and \fC*available_out\fP must specify the number of bytes addressable at \fC*next_in\fP and \fC*next_out\fP respectively\&. When \fC*available_out\fP is \fC0\fP, \fCnext_out\fP is allowed to be \fCNULL\fP\&. .PP After each call, \fC*available_in\fP will be decremented by the amount of input bytes consumed, and the \fC*next_in\fP pointer will be incremented by that amount\&. Similarly, \fC*available_out\fP will be decremented by the amount of output bytes written, and the \fC*next_out\fP pointer will be incremented by that amount\&. .PP \fCtotal_out\fP, if it is not a null-pointer, will be set to the number of bytes decompressed since the last \fCstate\fP initialization\&. .PP \fBNote:\fP .RS 4 Input is never overconsumed, so \fCnext_in\fP and \fCavailable_in\fP could be passed to the next consumer after decoding is complete\&. .RE .PP \fBParameters:\fP .RS 4 \fIstate\fP decoder instance .br \fIavailable_in\fP \fBin:\fP amount of available input; .br \fBout:\fP amount of unused input .br \fInext_in\fP pointer to the next compressed byte .br \fIavailable_out\fP \fBin:\fP length of output buffer; .br \fBout:\fP remaining size of output buffer .br \fInext_out\fP output buffer cursor; can be \fCNULL\fP if \fCavailable_out\fP is \fC0\fP .br \fItotal_out\fP number of bytes decompressed so far; can be \fCNULL\fP .RE .PP \fBReturns:\fP .RS 4 \fBBROTLI_DECODER_RESULT_ERROR\fP if input is corrupted, memory allocation failed, arguments were invalid, etc\&.; use \fBBrotliDecoderGetErrorCode\fP to get detailed error code .PP \fBBROTLI_DECODER_RESULT_NEEDS_MORE_INPUT\fP decoding is blocked until more input data is provided .PP \fBBROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT\fP decoding is blocked until more output space is provided .PP \fBBROTLI_DECODER_RESULT_SUCCESS\fP decoding is finished, no more input might be consumed and no more output will be produced .RE .PP .SS "void BrotliDecoderDestroyInstance (\fBBrotliDecoderState\fP * state)" .PP Deinitializes and frees \fBBrotliDecoderState\fP instance\&. .PP \fBParameters:\fP .RS 4 \fIstate\fP decoder instance to be cleaned up and deallocated .RE .PP .SS "\fBBrotliDecoderErrorCode\fP BrotliDecoderGetErrorCode (const \fBBrotliDecoderState\fP * state)" .PP Acquires a detailed error code\&. Should be used only after \fBBrotliDecoderDecompressStream\fP returns \fBBROTLI_DECODER_RESULT_ERROR\fP\&. .PP See also \fBBrotliDecoderErrorString\fP .PP \fBParameters:\fP .RS 4 \fIstate\fP decoder instance .RE .PP \fBReturns:\fP .RS 4 last saved error code .RE .PP .SS "\fBBROTLI_BOOL\fP BrotliDecoderHasMoreOutput (const \fBBrotliDecoderState\fP * state)" .PP Checks if decoder has more output\&. .PP \fBParameters:\fP .RS 4 \fIstate\fP decoder instance .RE .PP \fBReturns:\fP .RS 4 \fBBROTLI_TRUE\fP, if decoder has some unconsumed output .PP \fBBROTLI_FALSE\fP otherwise .RE .PP .SS "\fBBROTLI_BOOL\fP BrotliDecoderIsFinished (const \fBBrotliDecoderState\fP * state)" .PP Checks if decoder instance reached the final state\&. .PP \fBParameters:\fP .RS 4 \fIstate\fP decoder instance .RE .PP \fBReturns:\fP .RS 4 \fBBROTLI_TRUE\fP if decoder is in a state where it reached the end of the input and produced all of the output .PP \fBBROTLI_FALSE\fP otherwise .RE .PP .SS "\fBBROTLI_BOOL\fP BrotliDecoderIsUsed (const \fBBrotliDecoderState\fP * state)" .PP Checks if instance has already consumed input\&. Instance that returns \fBBROTLI_FALSE\fP is considered 'fresh' and could be reused\&. .PP \fBParameters:\fP .RS 4 \fIstate\fP decoder instance .RE .PP \fBReturns:\fP .RS 4 \fBBROTLI_TRUE\fP if decoder has already used some input bytes .PP \fBBROTLI_FALSE\fP otherwise .RE .PP .SS "\fBBROTLI_BOOL\fP BrotliDecoderSetParameter (\fBBrotliDecoderState\fP * state, \fBBrotliDecoderParameter\fP param, uint32_t value)" .PP Sets the specified parameter to the given decoder instance\&. .PP \fBParameters:\fP .RS 4 \fIstate\fP decoder instance .br \fIparam\fP parameter to set .br \fIvalue\fP new parameter value .RE .PP \fBReturns:\fP .RS 4 \fBBROTLI_FALSE\fP if parameter is unrecognized, or value is invalid .PP \fBBROTLI_TRUE\fP if value is accepted .RE .PP .SS "const uint8_t* BrotliDecoderTakeOutput (\fBBrotliDecoderState\fP * state, size_t * size)" .PP Acquires pointer to internal output buffer\&. This method is used to make language bindings easier and more efficient: .IP "1." 4 push data to \fBBrotliDecoderDecompressStream\fP, until \fBBROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT\fP is reported .IP "2." 4 use \fBBrotliDecoderTakeOutput\fP to peek bytes and copy to language-specific entity .PP .PP Also this could be useful if there is an output stream that is able to consume all the provided data (e\&.g\&. when data is saved to file system)\&. .PP \fBAttention:\fP .RS 4 After every call to \fBBrotliDecoderTakeOutput\fP \fC*size\fP bytes of output are considered consumed for all consecutive calls to the instance methods; returned pointer becomes invalidated as well\&. .RE .PP \fBNote:\fP .RS 4 Decoder output is not guaranteed to be contiguous\&. This means that after the size-unrestricted call to \fBBrotliDecoderTakeOutput\fP, immediate next call to \fBBrotliDecoderTakeOutput\fP may return more data\&. .RE .PP \fBParameters:\fP .RS 4 \fIstate\fP decoder instance .br \fIsize\fP \fBin:\fP number of bytes caller is ready to take, \fC0\fP if any amount could be handled; .br \fBout:\fP amount of data pointed by returned pointer and considered consumed; .br out value is never greater than in value, unless it is \fC0\fP .RE .PP \fBReturns:\fP .RS 4 pointer to output data .RE .PP .SS "uint32_t BrotliDecoderVersion (void)" .PP Gets a decoder library version\&. Look at BROTLI_VERSION for more information\&. .SH "Author" .PP Generated automatically by Doxygen for Brotli from the source code\&.